target/arm: Trap direct acceses to FPMR

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20260522220306.235200-14-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index d1a581acfd25994ca94ad9303db3df8ae62dd5ee..41dd01378431203842aac0cdf5d66d7e56a5b859 100644 (file)
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -2899,6 +2899,10 @@ static void handle_sys(DisasContext *s, bool isread,
     }
 
     if (!skip_fp_access_checks) {
+        if ((ri->type & ARM_CP_FPMR) && s->fpmr_el != 0) {
+            gen_exception_insn_el(s, 0, EXCP_UDEF, syndrome, s->fpmr_el);
+            return;
+        }
         if ((ri->type & ARM_CP_FPU) && !fp_access_check_only(s)) {
             return;
         } else if ((ri->type & ARM_CP_SVE) && !sve_access_check(s)) {